Testing at former landfill sites - Q&As

Prior to 1972, The City of Red Deer operated a number of small landfills throughout the city, and in many cases, the city has grown and developed around these former landfill sites. In 2015, The City completed the first stage of a project that involved the testing of nine former landfill sites that The City owned and operate in Red Deer. This testing was aimed to help The City better understand the potential impacts of former landfills on the environment and nearby properties.

The second phase of this project included testing of the former Montfort landfill site and took place in 2016-2017 after results from initial investigations showed potential for some landfill related effects to both the groundwater and soil vapour in the immediate vicinity of the former landfill site.

Questions and Answers

There are many sites in Red Deer that were once used to dump garbage. As the city grows we see more development taking place near these sites; therefore, The City of Red Deer initiated a project to assess former landfill sites in an effort to better understand the impacts and risks associated with (re)development near them. The project was a proactive City driven initiative that will enable us to make sound and timely decisions about (re)development near former landfills with the best and most current information possible. There were no regulatory requirements to do the project.

Yes. Development near former landfill sites has taken place in Red Deer and communities across Alberta with the province responsible for the regulations that dictate where people can develop in relation to landfills.

However, the regulations have changed over time. Prior to 1978 there were no development regulations that dictated setback distances when homes were constructed around existing landfill sites. In 1978, the province implemented regulations that required a 300 metre setback for homes from landfills; however, this technically only applied to operating landfill sites. In 1995, the regulations were clarified to include a 300 metre setback from inactive or closed landfill sites.

Potential risks with development in the vicinity of former landfill sites depend on a variety of factors, which include landfilling practices, age of the waste, type of waste, soils surrounding the waste and distance from the landfill.

With improvements in science and technology, we know more about the potential effects of buried waste on the environment and people’s health than we did 50 years ago. Knowledge about the potential risks associated with landfills has evolved over time.

Two potential risks associated with closed landfills include:

Contamination of groundwater by various chemicals present in buried wasteContaminants from former landfill sites can leach into groundwater; however, this is generally not a health concern for properties connected to City water. For those properties not connected to City water, the risk management report for those specific areas examined factors like direction of groundwater flow to determine if there is potential risk to well water.

Generation of landfill gasAs landfill materials decompose, landfill gas can be created and may migrate through the soil to collect in confined spaces, like basements. Methane is one of the primary components of landfill gas, and can pose an explosion risk at certain concentrations. Landfill gas can also contain various other trace gases, which have the potential to cause health impacts.

Investigation of the nine former landfill sites was conducted in a multi-stage approach:

Phase I: Environmental Site AssessmentAvailable information about each of the former landfill sites was reviewed and compiled, including landfilling practices, age of the waste, soils surrounding the waste, and type of developments and distance from the landfill (setbacks). To view these documents, visit the Landfill Risk Assessment Project page.

Phase II: Environmental Site AssessmentA physical investigation of the former landfill sites was conducted to determine the boundaries of waste disposal and collect samples of soil gas and groundwater. To view these documents, visit the Landfill Risk Assessment Project page.

Environmental Risk Management PlanThe data collected during the Phase I and II environmental site assessments was analyzed, and site specific risk management plans were developed. This data was also used to make recommendations on appropriate setback distances from each landfill site. To view these documents, visit the Landfill Risk Assessment Project page.

The Phase I and II environmental site assessments were completed in accordance with the Canadian Standards Association’s standards governing these types of reports. The Environmental Risk Management Plan was completed using Health Canada’s preliminary quantitative risk assessment model, which is a nationally accepted process for risk assessment.

RDC and Red Deer Motors (pdf)(Referred to as the former Red Deer Motors site because it was a landmark at the time. This name in no way indicates that Red Deer Motors was responsible for landfilling on the site)

Further testing was needed so that we could build upon the information we collected during the first stage of the project and ensure there were no changes or upgrades needed to mitigate risk near the former landfill sites.

Conditions in the groundwater and soil can change with the seasons as temperatures go up and down throughout the year; therefore, further testing was needed to build upon initial results and make decisions about development near former landfill sites today and in the future. This second stage of testing was necessary to understand any potential impacts to people’s health and safety as well as the environment.

In all homes where the indoor air was sampled, the chemicals that were tested for were not detected. This indicates the former Montfort landfill is not impacting the indoor air quality of adjacent homes in the Highland Green area.

The initial results did not include test results showing that adjacent properties were directly impacted. However, because we know that in some cases landfill gases can migrate through soil and collect in confined spaces The City chose to retain a consultant who undertook a more in depth process to fully understand what impact chemicals stemming from the former landfill site, if any, could have on properties and people living near the former landfill.

This testing occurred between December 2016 and March 2017 in an effort to collect information and samples across all seasons. While there are always chemicals that can be found in any groundwater and soil vapour, testing focused on measuring volatile organic compounds (VOCs) and methane at concentrations that could be harmful to people or property.

Testing included probes and wells on the former landfill site itself, and in selected backyards directly adjacent to the site. The final phase of testing occurred between March 8 and 14 with in-home air quality sampling of 10 properties that were selected based on their proximity to the former landfill site. In all cases, test results showed no chemicals from the former landfill site, in a concentration that could be harmful to people or property.

Throughout the process, The City of Red Deer worked with Alberta Health Services and Alberta Environment and Parks to determine where and how best to implement testing in the area. While no further indoor air testing is planned, further environmental monitoring will be conducted in 2017. The final report, compiling the seasonal data yet to be collected and the indoor air testing results and other results collected in March, is expected to be completed in Spring 2018.

The results are in, and it’s good news. In all homes where the indoor air was sampled, the chemicals that were tested for were not detected. This indicates the former Montfort landfill is not impacting the indoor air quality of adjacent homes in the Highland Green area. View the full report: Montfort Landfill Site - Indoor Air Sampling Report - June 2017 (pdf)

There are a variety of options, some simple and some complex, when it comes to mitigating the impacts and risks associated with landfill gas or groundwater contamination. If we find landfill gas or groundwater impacts in concentrations of concern, there are measures that can be put in place to manage the impacts associated with both. The City will work directly with residents to facilitate a plan and address the issue. The health and safety of citizens is our first priority.

There are a number of factors upon which property values are determined including the quality, size, features and age of your home, to name a few. However, the Municipal Government Act dictates how all assessments are legislatively required to be done in the province of Alberta. The valuation standard for residential assessments is market value but must be prepared using mass appraisal principles, which refers to the process of calculating assessed value for an entire group or groups of residential properties as of a specific date based on standardization and statistical testing versus individual appraisals on properties at different times. This project is about protecting property, people and the environment.

Alberta Environment supports the process The City undertook to assess risk related to former landfill sites, and Alberta Health Services is currently reviewing the full reports to gain a better understanding of potential health impacts. Alberta Health Services and Alberta Environment will continue to be involved as we carry out further testing over the next 24 months.

Applications for subdivision or development permits are subject to the current regulations regarding setbacks from landfill sites. In the case of the former Montfort (pdf)
landfill site as well as the former Red Deer College and Red Deer Motors (pdf)
sites, initial recommendations call for mitigation measures if (re)development takes place within 300 metres of the site. However, with further testing planned for each of the sites, these requirements would be addressed on a case by case basis.

If you are planning to subdivide or apply for a development permit for your property, please contact The City for guidance on the processes that may be required.